Azodyestuffs containing chromium and process of making



Patented Feb 24, 1931 HUGO SCHWEITZER, OF V EESDOEF-QN-THE-RHINE, ASSIGNOR TO GENERAL ANILINE \VORKS, INQ, OF NEVT YORK,

N. Y., A CORIPORATION OF DELAWARE AZODYESTUFFS CONTAINING CHROMIUM AND PROCESS OF MAKING No "Drawing. Application filed February 21, 1929, Serial No. 341,840, and in The present invention relates to color lakes or pigment dyestufis, and to a process of pre paring same, more particularly, it relates to compounds of the following general formula coon wherein R stands for an aromatic nucleus, at stands for the methyl or the carbox'ylic acid group, R stands for a phenyl nucleus wherein R and R may be substituted, and wherein the salicylic acid radicle is attached to the sulfone group in orthoor para-position in relation to the hydroxy group of the said radicle. By the symbol Cr in the specification and in the claims, I wish it not to be understood that one molecule chromium is attached to one molecule of the dyestufi, but Cr means that the dyestuff contains chromium in a complex combination; applicant cannot say with certainty in what combination the chromium is fixed, and in what quantity it is bound to one molecule of the dyestuff there may be attached one molecule to one molecule of the dyestufi, or less or more.

My new compounds are obtainable by boiling the aqueous solution of a dyestuif of the general formula:

COOH

wherein R stands for an aromatic nucleus, :0 stands for the methyl or the carboxylic' acid group, R stands for a phenyl nucleus, wherein R and R may be substituted, and where- 40 in the salicylic acid radicle is attached to the Germany February 25, 1928.

but at least one molecule of the chromium salt is used for each molecule of the dyestuff, generally I prefer to apply about one to two molecules. The dyestuffs is salted out from its solution in the usual manner, filtered and dried.

In the dry state, the new chromium complex compounds are yellowish powders which in the form of their alkali metal salts are watersoluble.

These new products, when dyed. on Wool are distinguished by yielding clear and greenish yellow shades, hitherto notv obtainable in this manner, and they possess a vvery satisfactory capacity for even dyeing and are of very satisfactory fastness to light, fulling, perspiration, steaming and 'carbonization. They are also useful as'lakes or pigment dyestufis on account of their excellent fastness to light, waterand lime.

The invention is illustrated by the follow- I ing' examples, but not limited thereto Example Z.60.5 parts by weight of the azo dyestuff obtainable by coupling diazotized 2-chloro-4-toluidine with a pyraZolone compound of the following formula:

said dyestulf having in its free form the following formula:

SOaH H3CC=N i are boiled for several hours under a reflux condenser with a chromium formate solution (in the proportion of one molecule of dyestuif and 12 molecules of the chromium salt). The dyestuff solution is filtered and the prod not is salted out, filtered and dried.

The dyestuff dyes wool a greenish yellow shade, it displays a satisfactory capacity for even dyeing and the dyeing is fastto light, fulling, perspiration steaming and carbonization.

Example 2.-62.5 parts by weight of the dyestuff prepared by coupling diazotized o-sulfanilic acid with a pyrazolone compound of the formula given in Example 1, said dyestuft' having in its free form the following formula:

OOOH

I on

are converted into the chromium complex compound in the manner disclosed in Example 1 and isolated and worked up according I to known methods.

The product dyes wool a greenish yellow tint, and displays fastness properties similar to those of the dyestulf obtained according to Example 1.

Complex chromium compounds of similar properties are obtainable from azo'dyestuft's formed by coupling diazo compounds of other aromatic bases, such as aniline, toluidines, xylidines, naphthylamines, or sulfonic wherein R stands for an aromatic nucleus, no '7 stands for the methyl or the carboxylic acid group, R stands for a phenyl nucleus wherein R, and B, may be substituted, and wherein the salicylic acid radicle is attached to the sulfone group in orthoor para-position in relation to the hydroXy group of the said radicle, with a water-soluble salt of trivalent chromium.

2. The process which comprises heating in aqueous solution an azodyestufi of the gen oral formula:

wherein R stands for an aromatic nucleus, m stands for the methyl or the carboxylic acid group, R stands for a phenyl nucleus, wherein R and R may be substituted, and wherein the salicylic acid radicle is attached to the sulfone group or orthoor para-position in relation to the hydroxy group of the said radicle, with at least an equi-molecular quantity of a watersoluble salt of trivalent chromium.

3. The process which comprises heating in aqueous solution one molecule of an azodyestuff of the general formula:

z-C=N wherein R stands for an aromatic nucleus, m

stands for the methyl or the carboxylic acid group, R stands for a phenyl nucleuswherein R and B may be substituted, and wherein the salicylic acid radicle is attached to the sulfone group in orthoor para-position in relation to the hydroxy group of the said radicle, with 1 to 2 molecules of a watersoluble salt of trivalent chromium.

- 4. The process which comprises heating in aqueous solution one molecule of the azodyestuif of the formula:

with 1 to 2 molecules of a watersoluble salt of trivalent chromium.

5. The process which comprises boiling for some hours an azodyestuff of the general formula:

-wherein R stands for an aromatic nucleus, :1: .stands for the methyl or the carboxylic acid group, R stands for a phenyl nucleus wherein R and R may be substituted, and wherein the salicylic acid radicle is attached to the sulfone group in orthoor para-position in relation to the hydroxy group of the said radicle,

with chromium formate in an aqueous solution 6. T he process which comprises boiling for some hours an azodyestufi' of the general formula:

OOOH

wherein R stands for an aromatic nucleus, 00 stands for the methyl or the carboxylic acid group, R stands for a phenyl nucleus wherein R and R may be substituted, and wherein the salicylic acid radicle is attached to the sulfone group in orthoor para-position in relation to the hydroxy group of the said radicle, with at least an equi-molecular quantity of chromium formate in aqueous solution.

7. The process which comprises boiling for some hours one molecule of an azodyestuff of the general formula:

UOOH

with 1 to 2 molecules of chromium formate in aqueous solution.

9. As new products azodyestufl's, containing chromium, of the general formula:

wherein R stands for an aromatic nucleus, :1: stands for the methyl or the carboxylic acid group, R stands for a phenyl nucleus wherein R and R may be substituted and wherein the salicylic acid radicle is attached to the sulfone group in orthoor para-position in relation to the hydroxy group of the said radicle said compounds being in a dry pulverized form yellowish powders, in the form of their alkali metal salts soluble in water, dyeing wool evenly clear, yellow shades of good fastness to light, fulling, perspiration, steaming and carbonization, and being suitable for use as lakes and pigment dyestufls.

10. As a new product the azodyestuff, containing chromium, having in its free form the formula:

said dyestuif being in a dry pulverized form a yellowish powder, in form of its alkali metal salts soluble in water, dyeing wool greenish yellow shades of good fastness to light, fulling, perspiration, steaming and carbonization, and being suitable for use as a lake and pigment dyestufl.

In testimony whereof I have hereunto set my hand.

HUGO SCHWEITZER. [L.s.] 

